Gaia 1 and 2. A pair of new Galactic star clusters

@article{Koposov2017Gaia1A,
  title={Gaia 1 and 2. A pair of new Galactic star clusters},
  author={Sergey E. Koposov and Vasily A Belokurov and Graeme Cambridge and Carnegie Mellon University},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2017},
  volume={470},
  pages={2702-2709}
}
We present the results of the very first search for faint Milky Way satellites in the Gaia data. Using stellar positions only, we are able to re-discover objects detected in much deeper data as recently as the last couple of years. While we do not identify new prominent ultra-faint dwarf galaxies, we report the discovery of two new star clusters, Gaia 1 and Gaia 2. Gaia 1 is particularly curious, as it is a massive (2.2$\times$10$^4$ M$_\odot$), large ($\sim$9 pc) and nearby (4.6 kpc) cluster… 

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